<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE html> <html lang="en"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>diagramscene.cpp Example File | Qt Widgets 5.12.6</title> <link rel="stylesheet" type="text/css" href="style/offline-simple.css" /> <script type="text/javascript"> document.getElementsByTagName("link").item(0).setAttribute("href", "style/offline.css"); // loading style sheet breaks anchors that were jumped to before // so force jumping to anchor again setTimeout(function() { var anchor = location.hash; // need to jump to different anchor first (e.g. none) location.hash = "#"; setTimeout(function() { location.hash = anchor; }, 0); }, 0); </script> </head> <body> <div class="header" id="qtdocheader"> <div class="main"> <div class="main-rounded"> <div class="navigationbar"> <table><tr> <td >Qt 5.12</td><td ><a href="qtwidgets-index.html">Qt Widgets</a></td><td ><a href="qtwidgets-graphicsview-diagramscene-example.html">Diagram Scene Example</a></td><td >diagramscene.cpp Example File</td></tr></table><table class="buildversion"><tr> <td id="buildversion" width="100%" align="right"><a href="qtwidgets-index.html">Qt 5.12.6 Reference Documentation</a></td> </tr></table> </div> </div> <div class="content"> <div class="line"> <div class="content mainContent"> <div class="sidebar"><div class="sidebar-content" id="sidebar-content"></div></div> <h1 class="title">diagramscene.cpp Example File</h1> <span class="subtitle">graphicsview/diagramscene/diagramscene.cpp</span> <!-- $$$graphicsview/diagramscene/diagramscene.cpp-description --> <div class="descr"> <a name="details"></a> <pre class="cpp"> <span class="comment">/**************************************************************************** ** ** Copyright (C) 2016 The Qt Company Ltd. ** Contact: https://www.qt.io/licensing/ ** ** This file is part of the examples of the Qt Toolkit. ** ** $QT_BEGIN_LICENSE:BSD$ ** Commercial License Usage ** Licensees holding valid commercial Qt licenses may use this file in ** accordance with the commercial license agreement provided with the ** Software or, alternatively, in accordance with the terms contained in ** a written agreement between you and The Qt Company. For licensing terms ** and conditions see https://www.qt.io/terms-conditions. For further ** information use the contact form at https://www.qt.io/contact-us. ** ** BSD License Usage ** Alternatively, you may use this file under the terms of the BSD license ** as follows: ** ** "Redistribution and use in source and binary forms, with or without ** modification, are permitted provided that the following conditions are ** met: ** * Redistributions of source code must retain the above copyright ** notice, this list of conditions and the following disclaimer. ** * Redistributions in binary form must reproduce the above copyright ** notice, this list of conditions and the following disclaimer in ** the documentation and/or other materials provided with the ** distribution. ** * Neither the name of The Qt Company Ltd nor the names of its ** contributors may be used to endorse or promote products derived ** from this software without specific prior written permission. ** ** ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR ** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT ** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, ** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT ** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, ** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY ** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE." ** ** $QT_END_LICENSE$ ** ****************************************************************************/</span> <span class="preprocessor">#include "diagramscene.h"</span> <span class="preprocessor">#include "arrow.h"</span> <span class="preprocessor">#include <QTextCursor></span> <span class="preprocessor">#include <QGraphicsSceneMouseEvent></span> DiagramScene<span class="operator">::</span>DiagramScene(<span class="type"><a href="qmenu.html">QMenu</a></span> <span class="operator">*</span>itemMenu<span class="operator">,</span> <span class="type"><a href="../qtcore/qobject.html">QObject</a></span> <span class="operator">*</span>parent) : <span class="type"><a href="qgraphicsscene.html">QGraphicsScene</a></span>(parent) { myItemMenu <span class="operator">=</span> itemMenu; myMode <span class="operator">=</span> MoveItem; myItemType <span class="operator">=</span> DiagramItem<span class="operator">::</span>Step; line <span class="operator">=</span> <span class="number">0</span>; textItem <span class="operator">=</span> <span class="number">0</span>; myItemColor <span class="operator">=</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>white; myTextColor <span class="operator">=</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>black; myLineColor <span class="operator">=</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>black; } <span class="type">void</span> DiagramScene<span class="operator">::</span>setLineColor(<span class="keyword">const</span> <span class="type"><a href="../qtgui/qcolor.html">QColor</a></span> <span class="operator">&</span>color) { myLineColor <span class="operator">=</span> color; <span class="keyword">if</span> (isItemChange(Arrow<span class="operator">::</span>Type)) { Arrow <span class="operator">*</span>item <span class="operator">=</span> qgraphicsitem_cast<span class="operator"><</span>Arrow <span class="operator">*</span><span class="operator">></span>(selectedItems()<span class="operator">.</span>first()); item<span class="operator">-</span><span class="operator">></span>setColor(myLineColor); update(); } } <span class="type">void</span> DiagramScene<span class="operator">::</span>setTextColor(<span class="keyword">const</span> <span class="type"><a href="../qtgui/qcolor.html">QColor</a></span> <span class="operator">&</span>color) { myTextColor <span class="operator">=</span> color; <span class="keyword">if</span> (isItemChange(DiagramTextItem<span class="operator">::</span>Type)) { DiagramTextItem <span class="operator">*</span>item <span class="operator">=</span> qgraphicsitem_cast<span class="operator"><</span>DiagramTextItem <span class="operator">*</span><span class="operator">></span>(selectedItems()<span class="operator">.</span>first()); item<span class="operator">-</span><span class="operator">></span>setDefaultTextColor(myTextColor); } } <span class="type">void</span> DiagramScene<span class="operator">::</span>setItemColor(<span class="keyword">const</span> <span class="type"><a href="../qtgui/qcolor.html">QColor</a></span> <span class="operator">&</span>color) { myItemColor <span class="operator">=</span> color; <span class="keyword">if</span> (isItemChange(DiagramItem<span class="operator">::</span>Type)) { DiagramItem <span class="operator">*</span>item <span class="operator">=</span> qgraphicsitem_cast<span class="operator"><</span>DiagramItem <span class="operator">*</span><span class="operator">></span>(selectedItems()<span class="operator">.</span>first()); item<span class="operator">-</span><span class="operator">></span>setBrush(myItemColor); } } <span class="type">void</span> DiagramScene<span class="operator">::</span>setFont(<span class="keyword">const</span> <span class="type"><a href="../qtgui/qfont.html">QFont</a></span> <span class="operator">&</span>font) { myFont <span class="operator">=</span> font; <span class="keyword">if</span> (isItemChange(DiagramTextItem<span class="operator">::</span>Type)) { <span class="type"><a href="qgraphicstextitem.html">QGraphicsTextItem</a></span> <span class="operator">*</span>item <span class="operator">=</span> qgraphicsitem_cast<span class="operator"><</span>DiagramTextItem <span class="operator">*</span><span class="operator">></span>(selectedItems()<span class="operator">.</span>first()); <span class="comment">//At this point the selection can change so the first selected item might not be a DiagramTextItem</span> <span class="keyword">if</span> (item) item<span class="operator">-</span><span class="operator">></span>setFont(myFont); } } <span class="type">void</span> DiagramScene<span class="operator">::</span>setMode(Mode mode) { myMode <span class="operator">=</span> mode; } <span class="type">void</span> DiagramScene<span class="operator">::</span>setItemType(DiagramItem<span class="operator">::</span>DiagramType type) { myItemType <span class="operator">=</span> type; } <span class="type">void</span> DiagramScene<span class="operator">::</span>editorLostFocus(DiagramTextItem <span class="operator">*</span>item) { <span class="type"><a href="../qtgui/qtextcursor.html">QTextCursor</a></span> cursor <span class="operator">=</span> item<span class="operator">-</span><span class="operator">></span>textCursor(); cursor<span class="operator">.</span>clearSelection(); item<span class="operator">-</span><span class="operator">></span>setTextCursor(cursor); <span class="keyword">if</span> (item<span class="operator">-</span><span class="operator">></span>toPlainText()<span class="operator">.</span>isEmpty()) { removeItem(item); item<span class="operator">-</span><span class="operator">></span>deleteLater(); } } <span class="type">void</span> DiagramScene<span class="operator">::</span>mousePressEvent(<span class="type"><a href="qgraphicsscenemouseevent.html">QGraphicsSceneMouseEvent</a></span> <span class="operator">*</span>mouseEvent) { <span class="keyword">if</span> (mouseEvent<span class="operator">-</span><span class="operator">></span>button() <span class="operator">!</span><span class="operator">=</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>LeftButton) <span class="keyword">return</span>; DiagramItem <span class="operator">*</span>item; <span class="keyword">switch</span> (myMode) { <span class="keyword">case</span> InsertItem: item <span class="operator">=</span> <span class="keyword">new</span> DiagramItem(myItemType<span class="operator">,</span> myItemMenu); item<span class="operator">-</span><span class="operator">></span>setBrush(myItemColor); addItem(item); item<span class="operator">-</span><span class="operator">></span>setPos(mouseEvent<span class="operator">-</span><span class="operator">></span>scenePos()); <span class="keyword">emit</span> itemInserted(item); <span class="keyword">break</span>; <span class="keyword">case</span> InsertLine: line <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qgraphicslineitem.html">QGraphicsLineItem</a></span>(<span class="type"><a href="../qtcore/qlinef.html">QLineF</a></span>(mouseEvent<span class="operator">-</span><span class="operator">></span>scenePos()<span class="operator">,</span> mouseEvent<span class="operator">-</span><span class="operator">></span>scenePos())); line<span class="operator">-</span><span class="operator">></span>setPen(<span class="type"><a href="../qtgui/qpen.html">QPen</a></span>(myLineColor<span class="operator">,</span> <span class="number">2</span>)); addItem(line); <span class="keyword">break</span>; <span class="keyword">case</span> InsertText: textItem <span class="operator">=</span> <span class="keyword">new</span> DiagramTextItem(); textItem<span class="operator">-</span><span class="operator">></span>setFont(myFont); textItem<span class="operator">-</span><span class="operator">></span>setTextInteractionFlags(<span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>TextEditorInteraction); textItem<span class="operator">-</span><span class="operator">></span>setZValue(<span class="number">1000.0</span>); connect(textItem<span class="operator">,</span> SIGNAL(lostFocus(DiagramTextItem<span class="operator">*</span>))<span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> SLOT(editorLostFocus(DiagramTextItem<span class="operator">*</span>))); connect(textItem<span class="operator">,</span> SIGNAL(selectedChange(<span class="type"><a href="qgraphicsitem.html">QGraphicsItem</a></span><span class="operator">*</span>))<span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> SIGNAL(itemSelected(<span class="type"><a href="qgraphicsitem.html">QGraphicsItem</a></span><span class="operator">*</span>))); addItem(textItem); textItem<span class="operator">-</span><span class="operator">></span>setDefaultTextColor(myTextColor); textItem<span class="operator">-</span><span class="operator">></span>setPos(mouseEvent<span class="operator">-</span><span class="operator">></span>scenePos()); <span class="keyword">emit</span> textInserted(textItem); <span class="keyword">default</span>: ; } <span class="type"><a href="qgraphicsscene.html">QGraphicsScene</a></span><span class="operator">::</span>mousePressEvent(mouseEvent); } <span class="type">void</span> DiagramScene<span class="operator">::</span>mouseMoveEvent(<span class="type"><a href="qgraphicsscenemouseevent.html">QGraphicsSceneMouseEvent</a></span> <span class="operator">*</span>mouseEvent) { <span class="keyword">if</span> (myMode <span class="operator">=</span><span class="operator">=</span> InsertLine <span class="operator">&</span><span class="operator">&</span> line <span class="operator">!</span><span class="operator">=</span> <span class="number">0</span>) { <span class="type"><a href="../qtcore/qlinef.html">QLineF</a></span> newLine(line<span class="operator">-</span><span class="operator">></span>line()<span class="operator">.</span>p1()<span class="operator">,</span> mouseEvent<span class="operator">-</span><span class="operator">></span>scenePos()); line<span class="operator">-</span><span class="operator">></span>setLine(newLine); } <span class="keyword">else</span> <span class="keyword">if</span> (myMode <span class="operator">=</span><span class="operator">=</span> MoveItem) { <span class="type"><a href="qgraphicsscene.html">QGraphicsScene</a></span><span class="operator">::</span>mouseMoveEvent(mouseEvent); } } <span class="type">void</span> DiagramScene<span class="operator">::</span>mouseReleaseEvent(<span class="type"><a href="qgraphicsscenemouseevent.html">QGraphicsSceneMouseEvent</a></span> <span class="operator">*</span>mouseEvent) { <span class="keyword">if</span> (line <span class="operator">!</span><span class="operator">=</span> <span class="number">0</span> <span class="operator">&</span><span class="operator">&</span> myMode <span class="operator">=</span><span class="operator">=</span> InsertLine) { <span class="type"><a href="../qtcore/qlist.html">QList</a></span><span class="operator"><</span><span class="type"><a href="qgraphicsitem.html">QGraphicsItem</a></span> <span class="operator">*</span><span class="operator">></span> startItems <span class="operator">=</span> items(line<span class="operator">-</span><span class="operator">></span>line()<span class="operator">.</span>p1()); <span class="keyword">if</span> (startItems<span class="operator">.</span>count() <span class="operator">&</span><span class="operator">&</span> startItems<span class="operator">.</span>first() <span class="operator">=</span><span class="operator">=</span> line) startItems<span class="operator">.</span>removeFirst(); <span class="type"><a href="../qtcore/qlist.html">QList</a></span><span class="operator"><</span><span class="type"><a href="qgraphicsitem.html">QGraphicsItem</a></span> <span class="operator">*</span><span class="operator">></span> endItems <span class="operator">=</span> items(line<span class="operator">-</span><span class="operator">></span>line()<span class="operator">.</span>p2()); <span class="keyword">if</span> (endItems<span class="operator">.</span>count() <span class="operator">&</span><span class="operator">&</span> endItems<span class="operator">.</span>first() <span class="operator">=</span><span class="operator">=</span> line) endItems<span class="operator">.</span>removeFirst(); removeItem(line); <span class="keyword">delete</span> line; <span class="keyword">if</span> (startItems<span class="operator">.</span>count() <span class="operator">></span> <span class="number">0</span> <span class="operator">&</span><span class="operator">&</span> endItems<span class="operator">.</span>count() <span class="operator">></span> <span class="number">0</span> <span class="operator">&</span><span class="operator">&</span> startItems<span class="operator">.</span>first()<span class="operator">-</span><span class="operator">></span>type() <span class="operator">=</span><span class="operator">=</span> DiagramItem<span class="operator">::</span>Type <span class="operator">&</span><span class="operator">&</span> endItems<span class="operator">.</span>first()<span class="operator">-</span><span class="operator">></span>type() <span class="operator">=</span><span class="operator">=</span> DiagramItem<span class="operator">::</span>Type <span class="operator">&</span><span class="operator">&</span> startItems<span class="operator">.</span>first() <span class="operator">!</span><span class="operator">=</span> endItems<span class="operator">.</span>first()) { DiagramItem <span class="operator">*</span>startItem <span class="operator">=</span> qgraphicsitem_cast<span class="operator"><</span>DiagramItem <span class="operator">*</span><span class="operator">></span>(startItems<span class="operator">.</span>first()); DiagramItem <span class="operator">*</span>endItem <span class="operator">=</span> qgraphicsitem_cast<span class="operator"><</span>DiagramItem <span class="operator">*</span><span class="operator">></span>(endItems<span class="operator">.</span>first()); Arrow <span class="operator">*</span>arrow <span class="operator">=</span> <span class="keyword">new</span> Arrow(startItem<span class="operator">,</span> endItem); arrow<span class="operator">-</span><span class="operator">></span>setColor(myLineColor); startItem<span class="operator">-</span><span class="operator">></span>addArrow(arrow); endItem<span class="operator">-</span><span class="operator">></span>addArrow(arrow); arrow<span class="operator">-</span><span class="operator">></span>setZValue(<span class="operator">-</span><span class="number">1000.0</span>); addItem(arrow); arrow<span class="operator">-</span><span class="operator">></span>updatePosition(); } } line <span class="operator">=</span> <span class="number">0</span>; <span class="type"><a href="qgraphicsscene.html">QGraphicsScene</a></span><span class="operator">::</span>mouseReleaseEvent(mouseEvent); } bool DiagramScene<span class="operator">::</span>isItemChange(<span class="type">int</span> type) { foreach (<span class="type"><a href="qgraphicsitem.html">QGraphicsItem</a></span> <span class="operator">*</span>item<span class="operator">,</span> selectedItems()) { <span class="keyword">if</span> (item<span class="operator">-</span><span class="operator">></span>type() <span class="operator">=</span><span class="operator">=</span> type) <span class="keyword">return</span> <span class="keyword">true</span>; } <span class="keyword">return</span> <span class="keyword">false</span>; } </pre> </div> <!-- @@@graphicsview/diagramscene/diagramscene.cpp --> </div> </div> </div> </div> </div> <div class="footer"> <p> <acronym title="Copyright">©</acronym> 2019 The Qt Company Ltd. Documentation contributions included herein are the copyrights of their respective owners.<br/> The documentation provided herein is licensed under the terms of the <a href="http://www.gnu.org/licenses/fdl.html">GNU Free Documentation License version 1.3</a> as published by the Free Software Foundation.<br/> Qt and respective logos are trademarks of The Qt Company Ltd. in Finland and/or other countries worldwide. All other trademarks are property of their respective owners. </p> </div> </body> </html>